The rise of renewable energy and electrified transportation drives demand for all-solid-state sodium-ion batteries with high safety and energy density. Among the materials investigated, NASICON-type Na 3 Zr 2 Si 2 PO 12 has emerged as a promising solid-state electrolyte due to its three-dimensional open-framework structure and superior Na + conductivity. This review provides a comprehensive analysis of the structural properties of Na 3 Zr 2 Si 2 PO 12 , with particular emphasis on the mechanisms by which various doping strategies influence ionic conductivity. Furthermore, a co-doping approach has been shown to lower activation energy via synergistic effects, thereby significantly improving ionic conductivity. Additionally, various preparation methods can effectively mitigate the formation of impurity phases and enhance material density. Doping-optimised NASICON electrolytes facilitate the development of all-solid-state sodium batteries with improved specific capacity and extended cycling stability. This study paves the way for high-performance solid-state electrolytes and proposes future research on multivariate co-doping and low-temperature sintering.
Dephosphorisation slag generally consists of a 2CaO·SiO 2 –3CaO·P 2 O 5 (C 2 S–C 3 P) solid solution, CaO–SiO 2 –FeO x glassy phase, and RO phase (FeO x , MgO and MnO). Its components, such as CaO, FeO x , MnO, and MgO, can be used as a soil conditioner in agriculture to improve acidic soil and supply nutrient elements. To promote its dissolution, CaO–SiO 2 –Fe 2 O 3 glassy phases with different Al 2 O 3 and Na 2 O contents were synthesised, and their dissolution behaviour and mechanism were investigated. The addition of Al 2 O 3 significantly inhibited the dissolution of the glassy phase because it increased the degree of polymerisation of the silicate network, and the glassy phase structure became more stable as the Al 2 O 3 content increased. When 3% Na 2 O was added, the dissolution ratios of elements from the glassy phase were the highest, with the dissolution ratio of Si reaching 21.0% and the dissolution ratios of Ca and Fe reaching 21.6% and 17.7% at pH 5. The substitution of CaO with Na 2 O significantly reduced the dissolution ratios of all elements. As the Na 2 O content increased, Na 2 O had a bigger influence on the silicate structure. Na 2 O addition enhanced the proportion of Q Si 2 units and formed additional bonds by interacting with non-bridging oxygens in the silicate tetrahedra, strengthening the stability of the glass network. Lowering pH increased the dissolution ratios of elements.
Pluronic F-127 based alumina-rice husk inks with different weight % of rice husk (1, 3, 5, 7.5, 10 wt.%) were prepared and rheological characteristic of the inks was studied. The concentration of rice husk in the solid content of the ink was 1.5%, 4.6%, 7.7%, 11.5%, and 15.4%. The gelation temperature was observed to decrease with an increase in rice husk wt.% from 23 degrees C to 7 degrees C. The XRD of the sintered sample showed the presence of quartz and nepheline derived from rice husk and alumina. The microstructure of sintered alumina showed that porosity increased with increasing rice husk content. The relative density of the samples sintered at 1350 degrees C and 1600 degrees C was observed to be between 80.6% and 62.5%, and between 83.8% and 76.3%. This study shows that the microstructure of 3D-printed parts can be tailored by adding rice husk to alumina-PF127 inks by direct ink writing.
Ceramic matrix composites (CMCs) in high-temperature environments have prominent nonlinear and hysteresis character-istics, which lead to the complexity of high-temperature vibration characteristics and difficulty of dynamic response simu-lation. Therefore, this study conducted a simulation analysis and experimental research on the vibration characteristics of2.5D woven C/SiC compositeflat-plate structures at different temperatures in an oxygen-free environment. Tensile, load-ing, and unloading tests and swept-frequency vibration tests were conducted on theflat-plate structure of CMCs underdifferent temperatures and oxygen-free environments, and an intrinsic model under arbitrary cyclic tensile and compressiveloads was established based on the characteristics of the stress-strain curves. The natural frequency of the CMCsfirstincreased and then decreased with increasing temperature. Finally, based on the macroscopic intrinsic model, the dynamicresponse was calculated using the centre difference method, and the maximum error of natural frequency was within 10%.
The article describes the performance of ring-type lead zirconate titanate (PZT) ceramics for accelerometer applications. In-house developed modified PZT powder was used for the fabrication of a ring-shaped sample. The samples were sintered at 1250 degrees C for 2 h, levelled, electrode and poled for 30 min. Piezoelectric charge constant (d33), dielectric constant (K), loss factor (tan delta) and Curie temperature (Tc) of the sample measured were 550 pC/N, 1752, 0.03 and 329 degrees C, respectively. Displacement versus applied voltage showed 1.06 & micro;m at a driving voltage of 1800 V. Saturation polarisation (Pr), maximum polarisation (Pmax) and coercive field (Ec) measured were 25.2 & micro;C/cm2, 33.5 & micro;C/cm2 and 8.5 kV/cm, respectively. The response of PZT ring samples in terms of output voltage was measured at different acceleration 'g' and frequencies. The output voltage versus 'g' graph shows very much linearity for all the test frequencies (500 Hz, 1 kHz, 5 kHz and 10 kHz). Maximum output voltage of 1885 mV was measured at 10 kHz and 20 g. Linear graph and better output of the ring samples imply that the developed PZT samples are very much suitable for accelerometer applications.
This study systematically investigates the high-temperature oxidation behaviour of (Zr,Ti,W)C-MexBy multiphase ceramics fabricated by spark plasma sintering, focusing on their performance in static air at 1000 degrees C-1100 degrees C (operating temperature range for divertor components in nuclear fusion devices). The oxide layers consist predominantly of t-TiO2, m-ZrO2 and (Ti, Zr)O-2/(Zr,Ti)O-2 solid solutions. At 1000 degrees C, oxidation follows parabolic kinetics, suggesting diffusion-controlled growth. At 1100 degrees C, linear kinetics prevail as enhanced volatilisation of WO3 and B2O3 leads to porous microstructures. The outer oxide layer develops voids due to WO3 sublimation, while the inner layer remains dense owing to B2O3 filling the pores and cracks. The multiphase oxide structure, comprising (Zr,Ti)O-2 and (Ti,Zr)O-2 solid solutions along with dispersed ZrO2 and TiO2 particles, substantially enhances the oxidation resistance. The incorporation of ZrB2 significantly increases the apparent activation energy of oxidation from 13.3641 kJ/mol (TW) to 47.4178 kJ/mol (TW60ZB), representing a 355% improvement in oxidation resistance. The key mechanisms include prolonged oxygen diffusion paths due to low-diffusivity ZrO2 regions, grain boundary pinning by interphase boundaries and microstress fields at TiO2/ZrO2 interfaces that deflect microcracks. These results demonstrate the promising potential of (Zr,Ti,W)C-MexBy ceramics for high-temperature applications such as nuclear fusion divertor components.
This study integrates JMP-based response surface methodology with multivariate regression to optimise process parameters and predict shrinkage behaviour in vat photopolymerization-printed alumina ceramics. The analysis highlights that coating thickness is an important factor in shrinkage control, while the relative importance of linear, interaction, and quadratic contributions varies with shrinkage mode. Results showed that the shrinkage rate in the length direction was mainly associated with the linear terms of coating thickness and scraper movement speed, with an additional contribution from their interaction. The width-direction shrinkage was primarily affected by the linear term of laser power, together with the interaction between laser power and coating thickness. The inner-diameter shrinkage was mainly governed by the quadratic term of scraper speed and the interaction between laser power and scraper speed, indicating a pronounced non-linear response. The volumetric shrinkage was predominantly influenced by quadratic terms, especially those associated with coating thickness, laser power, and laser scanning speed.
AlTiCN and AlTiCrN coatings were deposited on Ti6Al4V alloy (TA) using an arc ion plating, and their friction behaviour at high temperature was evaluated using a wear tester, which was used to investigate the oxidation resistance and tribological performance. The results indicate that the AlTiCN coating exhibits lower roughness and higher nanohardness compared with the AlTiCrN coating. The AlTiCN coating has better oxidation resistance compared with the AlTiCrN coating, which is attributed to the amorphous C in the coating. The average coefficients of friction of AlTiCN and AlTiCrN coatings are 0.287 +/- 0.02 and 0.379 +/- 0.03, respectively, and the corresponding wear rates are 1.75 +/- 0.2 and 7.17 +/- 0.7 mu m(3)& centerdot;N-1 & centerdot;mm(-1), respectively, demonstrating the superior tribological performance. The dominant wear mechanism is abrasive wear, accompanied by oxidative and fatigue wear, where the high hardness of nitrides and oxides plays a crucial role in resisting wear loss.
The present study explores the development and optimisation of graphene nanoplatelets (GNPs)-reinforced silicon nitride (Si3N4)-based composites to enhance material performance. The composites were synthesised utilising magnesium oxide and yttrium oxide as sintering additives via spark plasma sintering (SPS). The present study has the novelty that such combination of sintering additives has never been utilised to sinter GNPs-reinforced Si3N4 ceramics. Varying concentrations of GNPs were introduced into the Si3N4 matrix, and the resulting materials were extensively characterised using X-ray diffraction for phase analysis, Raman spectroscopy for carbon structure evaluation, and field-emission scanning electron microscopy for microstructural assessment. The results demonstrate that a low GNP content (0.5 wt%) leads to a simultaneous improvement in mechanical (peak hardness of 16.5 GPa), fracture toughness (6.7 MPa m(1/2)), tribological performance (wear volume = 0.027 mm(3), wear rate = 4.3 & times; 10(-8) mm(3).N-1.m(-1), and a mu(mean) approximate to 0.11 ), and thermal conductivity (64.8 W.m(-1)K(-1)) under identical SPS conditions. The study further elucidates the relationship between graphene dispersion, phase evolution, and property degradation at higher GNPs contents, providing a comprehensive assessment of the reinforcement efficiency of GNPs in Si3N4 ceramics.
Praseodymium oxide (Pr 6 O 11 ) (0.02 wt. %–0.06 wt. %) doped Ba (Zr 0.02 Ti 0.98 ) O 3 ceramics were synthesized by mixed oxide route using chemical precursors. The powders were calcined at 1100°C for a duration of 4 h. After calcination, the powders were de-agglomerated followed by granulation using 2 wt. % polyvinyl alcohol (PVA). The granules were pressed into pellets and subsequently sintered at 1450°C for 2 h. Microstructure analysis revealed well-developed grains in all the pellets. Further the samples were electroded, poled and characterized. The maximum piezoelectric coefficient ( d 33 ) achieved was 354 pC/N for 0.02 wt. % Pr 6 O 11 doped Ba(Zr 0.02 Ti 0.98 )O 3 and a relatively high dielectric constant ( K = 15117.2) measured at Curie temperature ( T c ) and 100 Hz frequency for the same composition. Additionally, these samples exhibited a higher positive strain of 0.64% at an electric field of 27.13 kV/cm could be a suitable lead-free piezo material for high strain and actuation application.
Today, additive manufacturing technology has brought revolutionary changes to the materials and manufacturing industries. While polymer printing and metal 3D printing have been extensively researched, ceramic printing has emerged as a new trend in research. Ceramic additive manufacturing not only shares the characteristics of additive manufacturing but also faces greater challenges due to the higher melting temperatures and inherent brittleness of ceramics compared to polymers and metals. Ceramic materials possess some excellent performance characteristics. Additive manufacturing technology makes it possible to produce complex ceramic parts with shorter production cycles, lower costs, and retaining the characteristics of traditionally manufactured products. This article introduces the specific working modes of ceramic additive manufacturing technology, including SL, DLP, TPP, DIW, FDM, UP, SLS/SLM, LOM, and BJ3DP printing technologies. The current research status of ceramic additive manufacturing is discussed, as well as the preparation of slurries and the basic requirements for successful ceramic printing.
The requirement for functional scaffolds made from hydroxyapatite-based materials is gaining importance in bone tissue engineering (BTE) due to their ability to provide mechanical behaviour similar to that of native tissue. Additive manufacturing (AM) via vat photopolymerisation (VPP) has been demonstrated to be a superior choice for fabricating FS, as it offers enhanced mechanical strength to support intricate structures with high printing resolution compared to other 3D printing methods. The current work presents a detailed review of different VPP AM processes to manufacture hydroxyapatite-based scaffolds for bone tissue engineering. The roles of various monomers, photoinitiators, and dispersants, as well as their impact on printability and the resulting scaffold properties, were elucidated. In addition, the debinding and sintering processes of scaffolds are elaborated. This review helps researchers and practitioners understand the latest advancements in VPP AM processes, photocurable resin technologies, and selection strategies for developing HAp scaffolds for BTE.
The inferior fracture toughness of high-entropy diboride ceramics (HEBs) severely limits their application in extreme environments. To address this challenge, nanoscale Al 2 O 3 was introduced as the reinforcement to improve the fracture toughness of (Hf 0.2 Zr 0.2 Ti 0.2 Ta 0.2 Cr 0.2 )B 2 and (Hf 0.2 Zr 0.2 Ti 0.2 Ta 0.2 Mo 0.2 )B 2 . Excellent mechanical properties were achieved for 15 vol% Al 2 O 3 doped (Hf 0.2 Zr 0.2 Ti 0.2 Ta 0.2 Cr 0.2 )B 2 and (Hf 0.2 Zr 0.2 Ti 0.2 Ta 0.2 Mo 0.2 )B 2 with a fracture toughness of 6.52 MPa·mm 1/2 , 6.78 MPa·mm 1/2 and a flexural strength of 518 MPa and 532 MPa, respectively. The strengthening/ toughening mechanisms can be ascribed to the pinning effect exerted by Al 2 O 3 particles that are uniformly distributed within the ceramic matrix. Furthermore, the incorporation of Al 2 O 3 substantially decreases the porosity of the ceramic material. This alteration facilitates a more thorough densification of the internal microstructure, which in turn markedly improves the mechanical responses of the HEBs. Besides, the inherent high-elastic modulus of Al 2 O 3 contributes to the flexural strength of the ceramic material, thereby further augmenting its mechanical properties.
The Sr(Ce 0.6 Zr 0.4 ) 0.85 Y 0.15 O 3−δ /Sm 0.2 Ce 0.8 O 1.9 (Strontium Cerium Zirconium Yttrium oxide [SCZY] and Samarium-doped Ceria [SDC]) co-ionic conducting composite electrolyte was successfully prepared by separately synthesising SCZY and SDC via the citrate-EDTA complexing method, followed by mechanical mixing through ball milling. After sintering at 1450 °C for 5 h, the composite exhibited a dense structure with retained integrity. Electrochemical and structural analyses were conducted under varied atmospheres and temperatures. The Pt/SCZY-SDC/Pt cell's total electrical conductivity and activation energy were determined using electrochemical impedance spectroscopy, yielding values of 0.039 S cm −1 and 61.56 kJ mol −1 , respectively, in H 2 /Air at 600–800 °C. Conductivity measurements indicated H + and O 2− ion conductivities of 0.228 and 0.00349 S cm −1 , respectively, at 800 °C. Notably, the electrolyte-supported Pt/SCZY-SDC/Pt cell demonstrated a power output of 21.7 mW cm −2 and an open-circuit voltage of 0.74 V at 800 °C, featuring a 1.19-mm electrolyte thickness and 2.54 cm 2 cathode area.
A polycrystalline sample of Sr(Mn 1/2 Nb 1/2 )O 3 (SMNO) was synthesised via the solid-state reaction method, confirming a single-phase perovskite structure. Room-temperature XRD analysis revealed a tetragonal crystal system. Micro-Raman spectroscopy exhibited broad peaks, suggesting the presence of a vibrational band and ferroelectric characteristics. Dielectric properties were investigated over a broad frequency (100–1 MHz) and temperature (24–360°C) range, revealing strong low-frequency dispersion, a very high dielectric constant and loss (∼6). A broad permittivity peak was observed at 280°C across all measured frequencies. The frequency and temperature dependence of the ac conductivity (σ ac ) suggest a thermally activated relaxation mechanism. Impedance spectroscopy indicated that the dielectric and conductive properties of the material arise from the contributions of bulk, grain boundaries and electrode effects. Magnetic measurements identified an antiferromagnetic transition at 41 K, co-existing with a low-temperature ferromagnetic phase. The growing demand for miniaturised and versatile electronic components drives our strong interest in developing dielectric ceramics. These materials are critical for applications such as capacitors, sensors, actuators and transducers.
The preparation of ceramsite using lead-zinc tailings (LZT) as the primary raw material, fly ash as a sintering auxiliary material, and coal powder as a flux was investigated. The results indicate that the apparent density and water absorption of ceramsite decrease continuously with increasing sintering temperature, while the cylinder compressive strength shows the opposite trend. As the LZT content increases, the apparent density of ceramsite initially decreases and then slightly increases. Meanwhile, the water absorption rate shows an upward trend, and the cylinder compressive strength continuously declines. The primary crystalline phases of LZT-based ceramsite are anorthite, mullite and quartz, with mullite providing significant support to the strength of the ceramsite. Under the conditions of 50% LZT content and a sintering temperature of 1250 degrees C, the ceramsite with an apparent density of 1165.8 kg/m3, a water absorption of 3.1%, and a cylinder compressive strength of 8.5 MPa was successfully produced.
A polycrystalline sample of Sr(Mn1/2Nb1/2)O-3 (SMNO) was synthesised via the solid-state reaction method, confirming a single-phase perovskite structure. Room-temperature XRD analysis revealed a tetragonal crystal system. Micro-Raman spectroscopy exhibited broad peaks, suggesting the presence of a vibrational band and ferroelectric characteristics. Dielectric properties were investigated over a broad frequency (100-1 MHz) and temperature (24-360 degrees C) range, revealing strong low-frequency dispersion, a very high dielectric constant and loss (similar to 6). A broad permittivity peak was observed at 280 degrees C across all measured frequencies. The frequency and temperature dependence of the ac conductivity (sigma(ac)) suggest a thermally activated relaxation mechanism. Impedance spectroscopy indicated that the dielectric and conductive properties of the material arise from the contributions of bulk, grain boundaries and electrode effects. Magnetic measurements identified an antiferromagnetic transition at 41 K, co-existing with a low-temperature ferromagnetic phase. The growing demand for miniaturised and versatile electronic components drives our strong interest in developing dielectric ceramics. These materials are critical for applications such as capacitors, sensors, actuators and transducers.
A modified two-step sintering process is compared with the conventional two-step sintering process for sintering alumina. In modified two-step sintering, the first step was heated with microwave-assisted conventional heating up to 1500 degrees C (T-1) and the second step was heated at 1450 degrees C (T-2) with conventional heating alone. T-1 and T-2 were maintained the same for both the modified two-step sintering and conventional two-step sintering processes. Results showed that modified two-step sintering produced marginally lesser grain growth but similar densification. A near-full densification (>99%) was obtained on the holding sample for 3 h at T-2 in both the two-step sintering processes. A minimum grain size of 1.7 and 1.9 mu m and a maximum grain size of 3.0 and 3.2 mu m were obtained at 0.5 and 3 h sintering durations, respectively, for both processes. Modified two-step sintering produced a Vickers hardness of 18.7 +/- 0.2 GPa, and the conventional two-step sintering process produced a hardness of 18.5 +/- 0.2 GPa.
The addition of a ternary alkali agent composed of sodium hydroxide, sodium aluminate and calcium hydroxide in the sintering process of ceramic tile fabrication was proposed. Sewage sludge acid-leaching residue and waste bottle glass were used as raw materials. The results indicated that the addition of 6 M sodium hydroxide, 6 wt-% sodium aluminate and 8 wt-% calcium hydroxide reduced the sintering temperature from 1100 degrees C to 750 degrees C and enhanced the performance of the produced ceramic tile. Under optimal conditions with an sewage sludge acid-leaching residue:waste bottle glass mixing ratio of 1:2, solid-liquid mass ratio = 2:1 (g/g), and sintering duration of 75 min, the produced ceramic tile achieved a bending strength of 6.5 MPa, bulk density of 1.61 g/cm3, water absorption of 12.5% and porosity of 12.5%. This study demonstrates that ceramic tiles can be produced through a cleaner process while simultaneously achieving waste valorisation of sewage sludge acid-leaching residue and waste bottle glass.
This study evaluated the effects of screw hole and preparation techniques on the fracture resistance of implant-supported translucent zirconia crowns after mechanical cycling. Forty crowns were divided into four groups of 10: CNH (cement-retained with no screw access hole) for the control, HBS (hole prepared before dense sintering), HAS (hole manually prepared after sintering), and HRS (hole manually prepared undergo resintered). All crowns survived 360,000 cycles with a peak force of 300 N at 10 Hz. Fracture resistance assessments indicated that the HBS technique exhibited the highest resistance, with CNS demonstrating the lowest. However, statistical analyses (Kruskal-Wallis and Mann-Whitney U tests) revealed no significant differences between them. SEM fractographic analysis indicated that screw hole preparation techniques could influence fracture patterns and failure initiation in zirconia crowns.
